soul

the principle of life, feeling, thought, and action in humans, regarded as a distinct entity separate from the body, and commonly held to be separable in existence from the body; the spiritual part of humans as distinct from the physical part.

the spiritual part of humans regarded in its moral aspect, or as believed to survive death and be subject to happiness or misery in a life to come: arguing the immortality of the soul.

the disembodied spirit of a deceased person: He feared the soul of the deceased would haunt him.

"A substantial entity believed to be that in each person which lives, feels, thinks and wills" [Century Dictionary], Old English sawol "spiritual and emotional part of a person, animate existence; life, living being," from Proto-Germanic *saiwalo (cf. Old Saxon seola, Old Norse sala, Old Frisian sele, Middle Dutch siele, Dutch ziel, Old High German seula, German Seele, Gothic saiwala), of uncertain origin.

Sometimes said to mean originally "coming from or belonging to the sea," because that was supposed to be the stopping place of the soul before birth or after death [Barnhart]; if so, it would be from Proto-Germanic *saiwaz (see sea). Klein explains this as "from the lake," as a dwelling-place of souls in ancient northern Europe.

Meaning "spirit of a deceased person" is attested in Old English from 971. As a synonym for "person, individual, human being" (e.g. every living soul) it dates from early 14c. Soul-searching (n.) is attested from 1871, from the phrase used as a past participle adjective (1610s). Distinguishing soul from spirit is a matter best left to theologians.

n.2

"instinctive quality felt by black persons as an attribute," 1946, jazz slang, from soul (n.1). Also from this sense are soul brother (1957), soul sister (1967), soul food (1957), etc. Soul music, essentially gospel music with "girl," etc., in place of "Jesus," first attested 1961; William James used the term in 1900, in a spiritual/romantic sense, but in reference to inner music.